Optimized Design Of Production String For Drainage Gas Production And Recompletion In The Offshore XD Gas Field

The XD Gas Field has gradually entered to the middle or late stage of production,because of the decrease of formation pressure,the production adjustment and increased activity of edge bottom water,the problem of liquid loading is becoming more and more serious.After the water breakthrough,XD Gas Field reduces production by 127×104m3/d,which severely constrained on its production.In order to ensure stable production in the middle and late stage of XD Gas Field,it is necessary to carry out the optimal design of drainage gas recovery scheme by "one well,one policy" classification.Combining with the production situation of XD Gas Field,this paper analyzes the main problems that will be faced when selecting measures in XD Gas Field,and based on these,through process analysis,demonstration of optimized computing,software simulations and other ways,the current mature 12 types of drainage technology has been demonstrated.The appropriate measures have been selected by "one well,one policy".Meanwhile by optimizing the calculation model of the minimum critical liquids carrying flow rate in XD Gas Field,the timing prediction of the effusion occurrence has been carried out in the case wells,which provides guidance for the implementation time of the drainage project.On the basis of the feasible project of single well drainage,this paper designs an optional drainage gas recovery project under the condition of three kinds of motionless pipe columns for XD Gas Field:1.Foaming-ball foam drainage gas recovery project;2.The upper and lower parts of the safety valve hanging velocity string drainage gas recovery project;3.The upper parts of the safety valve hanging vortex tools and lower parts hanging velocity string.Taking A5H and A20H wells as examples,design the optimal drainage project of the well.Considering the problems that may exist in gas wells' liquid carrying in the whole production lifetime,this paper puts forward a new method of replacing string drainage:double tubing well completion method.Based on the establishment of wellbore pressure drop model and output equivalent analysis calculation model,carried out the output equivalence analysis and verification of double tubing production pipe string,the adaptability of the method in XD Gas Field is analyzed from the feasibility of the structure of the completion pipe string,and the optimization design of the discharge method under the condition of replacing pipe string is carried out with the example of XD-A5H.Based on the advantages of the double tubing completion and recovery scheme proposed in this paper,this paper eliminates the technical problems of drainage and gas recovery in the middle and late stage of single-pipe column completion production,and further analyzes the feasibility of double tubing completion pipe string from the point of view of deep water gas well completion,which provides a new idea for the production of non.